Introduction. Reg ts 
‘call spirits from the vasty deep.” I resolved 
therefore to summon those of the most learned 
alchymists of the past, and to commune with 
them, that I might have the shades of these 
distinguished men before me while my lamp 
was burning,—nay, even while my efforts to 
transmute the baser metals into gold were 
progressing. 
Firstly, I called up that great Arabian 
Alchymist, Gebir, who has been worthily 
called a “captayne and a prince of this 
science.” I found him affable and ready to 
give me any hints in his power, a great 
scholar and learned in all the sciences. His 
famous work the Summa Perfectionis, or 
Lapis Philosophorum, was of great assistance 
to me. My next visitor was our own country- 
man, Roger Bacon (1214-1292). I found 
his society all I could wish. A Franciscan 
Monk, but one who had evidently devoted 
more of his thoughts to alchymic research 
than to his religious duties, he held a most 
